Steca Solarix 2020-x2 User manual

Solar charge controller
Solar charge controller for
two batteries 12 V/24 V 20 A
Installation and operating instructions
EN
751.792 | Z01 | 1504

EN About these operating instructions
2 751.792 | Z01 | 1504
Contents
1About these operating instructions...........................................2
2Safety ........................................................................................3
3Description ................................................................................4
4Installation ................................................................................7
5Maintenance ...........................................................................12
6Self test ...................................................................................12
7Faults and remedies ................................................................13
8Technical data .........................................................................18
9Commercial and legal guarantee conditions ...........................22
1About these operating instructions
These operating instructions are part of the product.
Read these operating instructions carefully before use.
Keep these operating instructions in the vicinity of the
product over the entire lifetime of the product.
Pass these operating instructions on to every subsequent user
of the product.
1.1 Description of symbols
Safety instructions are labelled as follows:
Keyword
Measures for avoiding danger
Instructions relating to the functional safety of the system are in
bold type.

Safety EN
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2Safety
2.1 Designated use
The solar charge controller may only be used for charging
and controlling lead-acid batteries (with liquid or solid
electrolyte).
The solar charge controller may only be connected to a solar
generator (solar module or array of solar modules within the
limits of the permissible connection values) and must not be
connected to any other energy source.
The specifications of the solar charge controller and the
connected components listed in these operating instructions
must be adhered to.
The manufacturer’s specifications for the solar modules and
batteries must be adhered to.
2.2 General safety instructions
Follow the general and national safety and accident
prevention regulations.
The factory-applied labels on the device must not be
modified or removed.
Keep children away from photovoltaic systems.
Do not open the device.

EN Description
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Danger of fire and explosion
Do not use the solar charge controller in any of the
following situations:
- In dusty environments
- In the vicinity of solvents
- In environments where inflammable gases and
vapours can be present
Do not expose the batteries to open flames or sparks.
Ensure that the room is adequately ventilated.
Perform regular checks to ensure that the system is
functioning (charging) correctly.
Follow the charging instructions of the battery
manufacturer.
3Description
The solar charge controller utilises the electrical power
generated by solar modules for charging two batteries and for
directly supplying electrical loads.
Product features:
Automatic voltage adjustment 12 V/24 V DC
Charging of main and auxiliary batteries
Monitoring of the charge state of the batteries
Dynamic charge control depending on the charge state of the
batteries (charging priority given to the main battery)
Automatic switch-on after shutdown
Suitable for systems with negative pole connected to
common ground
Solar charge controller provides overcharge protection and
deep discharge protection for the batteries
Automatic monthly maintenance charge
Hibernation mode
Separate load circuit for external loads (can only be used
when the main battery is sufficiently charged; indicated by
LED 4 lit up yellow or green at the load output)

Description EN
751.792 | Z01 | 1504 5
USB charge socket (e.g. for charging a mobile phone)
Can be expanded with an external remote display
Can be integrated into the StecaLink bus system
Structure:
1 LED 1 and terminal block for auxiliary battery (battery II)
2 LED 2 and terminal block for solar module
3 LED 3 and terminal block for main battery (battery I)
4 LED 4 and terminal block for connecting loads (load circuit)
5 Plastic housing
6 Connection for StecaLink bus system
7 USB charge socket
8 Fastening holes (4 holes)
The solar charge controller can be used indoors and in vehicles.
The charging programme is optimised for one main battery and
one auxiliary battery.
All types of lead-acid batteries can be connected (with liquid or
solid electrolyte).

EN Description
6 751.792 | Z01 | 1504
When only one battery is used then this must be connected to
the main battery terminals.
The charging times depend on the power provided by the solar
module and the capacity of the battery.
With a maximum load current of 20 A the load circuit is suitable
for external appliances with a power rating of up to 240 W at
12 V and 480 W at 24 V.
The solar charge controller begins operating as soon as a battery
is connected. If the solar module delivers no voltage for more
than 48 hours, the solar charge controller will enter hibernation
mode (all LEDs are deactivated). When a voltage is delivered
again by the solar module, the charge controller will resume
functioning again within 30 minutes.
The user does not need to operate the solar charge controller or
make any settings.
Four multicolour LEDs indicate the operating status, charge state
and any faults that may occur (see “Faults and remedies”).
LED displays
Battery charge
state
LED 1 and LED 3
displays
(solar module
not charging)
LED 1 and LED 3 dis-
plays
(solar module
charging)
100 %
Green flashing1)
Green slowly alternating
between bright/dark
Green fully lit2)
50 %
Yellow fully lit
Yellow slowly alternating
between bright/dark
0 %
Red fully lit3)
Red slowly alternating
between bright/dark
Red flashing4)
1 ) Cut-off voltage reached, excess energy available
2 ) Charge state: fully charged
3 ) Charge state: low charge
4 ) Battery deeply discharged

Installation EN
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LED 2
Solar module
Meaning
Green fully lit
Solar module connected, no charging
current flowing
Green slowly alternating
between bright/dark
Charging current flowing
Yellow fully lit
Solar module voltage too low
Off
Solar module voltage below 8 V
LED 4
Load circuit
Meaning
Green fully lit
Load switched on
Green slowly alternating
between bright/dark
Special function switched on (only in
conjunction with an optional external
remote display)
Yellow fully lit
Pre-warning: battery weak
Off
Load circuit switched off to protect
the batteries
4Installation
Danger of fire and explosion
The solar charge controller may only be connected to
loads and the batteries by suitably trained and qualified
personnel in accordance with the applicable regulations.
The installation and operating instructions for all com-
ponents of the photovoltaic system must be observed.
Ensure that no cables are damaged.
Do not mount the solar charge controller outdoors or in wet
rooms.
Do not subject the solar charge controller to direct solar
irradiation or other sources of heat.
Protect the solar charge controller from dirt and moisture.

EN Installation
8 751.792 | Z01 | 1504
Mount the solar charge controller upright on a non-
inflammable surface.
Maintain a minimum clearance of 10 cm above and below
the unit to ensure free circulation of air.
Mount the solar charge controller as close as possible to the
batteries (but with a safety clearance of at least 30 cm).
Step 1 Mounting the solar charge controller
1. Use the drilling template to mark the hole positions on the
wall.
2. Drill 4 holes (Ø depending
on the wall material and
the fasteners used).
3. Use 4 suitable screws (not
provided) to fasten the con-
troller to the wall. The cable
openings must face down-
wards.
Step 2 Connecting the solar charge controller
Danger of fire and explosion
Solar modules generate electricity under incident light.
The full voltage is present, even when the incident light
levels are low. You must therefore protect the solar
modules from incident light during installation, e.g.
cover them.
Do not touch exposed cable ends.
Take care to ensure that the cables do not touch each
other.
Use only insulated tools.
Ensure that all loads to be connected are switched off.
Connections must always be made in the sequence
described below.
Ø approx. 5 mm

Installation EN
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Cable cross sections
Distance
3 m
5 m
10 m
Current
20 A
4 mm²
6 mm²
10 mm²
10 A
2.5 mm²
4 mm²
6 mm²
5 A
2.5 mm²
2.5 mm²
4 mm²
The specified cable cross sections are minimum values. Please choose
somewhat higher cross sections (max. 10mm²) for a higher efficiency.
Cable terminal tighten-
ing torque
1.2 Nm
Cable lengths
Max of 10 m for solar module connection
cable
Max of 2 m for battery connection cable
Max of 10 m for load connection cable
Reference potential
Common negative pole (negative pole connect-
ed to common ground), earthing is not re-
quired
Fuse
30/40 A
Load output
240 Wmax(12 V)
480 Wmax(24 V)
Umax=60 V
Imax=20 V
Fuse
30/40 A
max. 2 m
2.5-10 mm²
max. 10 m
2.5-10 mm²
max. 2 m
2.5-10 mm²
2.5-10 mm²
max. 10 m

EN Installation
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Connecting the batteries (first battery I, then battery II)
The main battery is connected to “Battery I”, the auxiliary
battery is connected to “Battery II”.
1. Label the battery connection cables as a plus cable (B1+ or
B2+) and a minus cable (B1- or B2-).
2. Lay the battery connection cables parallel to each other
between the solar charge controller and the batteries, but do
not yet connect them.
3. Install a 30 A (for a cable cross-section of 6 mm2) or 40 A (for
a cable cross-section of 10 mm2) fuse with fuse holder in the
plus cable as close as possible to the battery pole.
(The fuse holder is not included in the scope of delivery.)
4. Remove the fuse from the fuse holder.
5. Connect the battery connection cables with the correct
polarity to the terminal pairs with the corresponding battery
symbol (battery I or battery II).
6. Connect the plus cable to the positive pole of the battery.
7. Connect the minus cable to the negative pole of the battery.
The negative pole can be earthed if required.
8. Insert the external fuse
When the battery is correctly connected, LED 1 or LED 3 lights
up green, yellow or red depending on the charge state. LED 4
lights up green or yellow depending on the charge state of the
main battery.
Connecting the solar module
1. Ensure that the solar module is protected from incident light.
2. Label the solar module connection cables as a plus cable
(M+) and a minus cable (M–).
3. Lay the two solar module connection cables parallel to each
other between the solar module and the solar charge
controller, but do not yet connect them.
4. Connect the plus cable M+ with the correct polarity to the
solar module terminal pair on the solar charge controller.

Installation EN
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5. Connect the minus cable M- with the correct polarity to the
solar module terminal pair on the solar charge controller.
6. Remove the covering from the solar module.
When the solar module is correctly connected, LED 2 lights up
green (permanently or alternating between bright/dark).
Connecting loads
Loads that must not be deactivated by the solar charge
controller deep discharge protection, e.g. emergency lights or
radio connection, can be connected directly to the battery and
separately fused.
1. Ensure that the loads are switched off and the corresponding
fuses are removed.
2. Label the load connection cables as a plus cable (L+) and a
minus cable (L–).
3. Lay the load connection cables parallel to each other
between the solar charge controller and the loads, but do not
yet connect them.
4. First connect the L+ load cable with the correct polarity to
the right pair of terminals on the solar charge controller (with
the lamp symbol).
5. Then connect the L- load cable with the correct polarity to
the right pair of terminals on the solar charge controller (with
the lamp symbol).
6. Replace any removed fuses and then switch on the loads.
When the loads are correctly connected, LED 4 remains lit in
green or yellow.
Step 3 Completion work
1. Secure all cables in the immediate vicinity of the solar charge
controller using strain relief fittings (clearance of approx.
10 cm).
2. Check the LED displays.
The solar charge controller is ready for operation.

EN Maintenance
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5Maintenance
Clean the solar charge controller as necessary using a brush
or soft cloth. Do not use water for cleaning.
Ensure adequate ventilation at the rear side of the housing
(heatsinks).
Check the cable strain relief.
Check that all cable connections are secure. Tighten screws if
necessary.
Check all terminals for signs of corrosion.
All components of the photovoltaic system must be checked
at least annually, according to the specifications of the
respective manufacturers.
6Self test
A self test of the solar charge controller can be executed if
required. An adjustable, stabilised power supply unit with
current limiting is required for the self test.
1. Disconnect all connections to the solar charge controller and
wait for at least 1 minute.
2. Adjust the power supply to a voltage of 7.25 V (± 0.25 V)
and set the current limit to max. 2 A (0.5 A to 2 A).
3. Connect the power supply unit with the correct polarity to
the solar module terminals.
The self test starts automatically. The results are displayed
according to the following table:
Display
Meaning
LEDs 1 to 4 flash green
Self test passed, no device faults
LEDs 1 to 4 flash red
Internal power supply fault or tem-
perature sensor fault
LED 1 flashes red
Fault in auxiliary battery charge
control

Faults and remedies EN
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Display
Meaning
LED 2 flashes red
Defective USB charge socket
LED 3 flashes red
Fault in main battery charge control
LED 4 flashes red
Defective load switch
7Faults and remedies
After a shutdown the supply to the loads in the load circuit and
the battery charging are resumed as soon as the conditions
causing the shutdown are again within a permissible range.
Please consult your point of sale if the fault cannot be corrected
using the measures described.
Fault display LEDs

EN Faults and remedies
14 751.792 | Z01 | 1504
Error/
Fault message
Cause
Remedy
No display
Hibernation
mode active
- Check solar module
voltage
- Wait 30 minutes
Battery voltage
too low
Charge the battery
The external fuse
in the battery
connection cable
has blown
Replace the external fuse
Battery (Battery I)
not connected
- Disconnect all connec-
tions
- Connect a (new) bat-
tery
- Reconnect the solar
module and loads
Battery is defec-
tive
LEDs 1 and 3
flash red,
LEDs 2 and 4
flash yellow
Internal power
supply fault or
temperature
sensor fault
Replace the solar charge
controller
LEDs 1 to 4
flash yellow/red
Shutdown due to
overtemperature
Check the load circuit for
overload and/or reduce
the load if necessary

Faults and remedies EN
751.792 | Z01 | 1504 15
Error/
Fault message
Cause
Remedy
Load circuit
LED 4 lights up
red
Short circuit in
load circuit
- Disconnect loads
- Correct the cause of
the short circuit
- Reconnect loads
LED 4 flashes
red (slowly)
Overload warning
Reduce current con-
sumption of the loads, if
necessary switch off or
disconnect loads
LED 4 flashes
red (fast)
Shutdown due to
overload
Reduce current con-
sumption of the loads, if
necessary switch off or
disconnect loads
LED 4 off
Shutdown due to
battery un-
dervoltage
- Charge the battery
- Equip loads directly
connected to the bat-
tery with deep dis-
charge protection
- Check the battery and
replace if necessary

EN Faults and remedies
16 751.792 | Z01 | 1504
Error/
Fault message
Cause
Remedy
Battery
LED 1 and/or
LED 3 lights up
blue
Battery is con-
nected with the
wrong polarity
Connect the battery
with the correct polarity
LED 1 and/or
LED 3 flashes
red/green
Battery overvolt-
age
- Disconnect the battery
- Correct the cause of
the overvoltage
- Reconnect the battery
LED 1 and LED 3
flash red alter-
nately
Impermissible
battery combina-
tion
24 V battery
(battery I) and
12 V battery
(battery II)
- Disconnect the batter-
ies
- Connect a permissible
battery combination

Faults and remedies EN
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Error/
Fault message
Cause
Remedy
Solar module
LED 2 lights up
blue
Solar module
connected with
incorrect polarity
Connect the solar mod-
ule with the correct
polarity
LED 2 lights up
red
Short circuit at
solar module
input
Correct the cause of the
short circuit
LED 2 flashes
red (slowly)
Solar module
overcurrent
- Disconnect the solar
module
- Correct the cause of
the overcurrent
- Reconnect the solar
module
LED 2 flashes
red (fast)
Shutdown due to
overcurrent
- Disconnect the solar
module
- Correct the cause of
the overcurrent
- Reconnect the solar
module
LED 2 flashes
red/green
Solar module
overvoltage
- Disconnect the solar
module
- Correct the cause of
the overvoltage
- Reconnect the solar
module

EN Technical data
18 751.792 | Z01 | 1504
8Technical data
General information
Dimensions
190 mm x 120 mm x 58 mm
Weight
500 g
Current consumption
Approx. 20 mA
Reference potential
Minus
Earthing
The negative pole can be
earthed but this is not essen-
tial. Never earth the plus pole!
Maximum heatsink tempera-
ture (rear side of unit)
70 °C
Protection class
IP 31
Ambient temperature Tamb
-20 °C to +50 °C
Power limiting possible at
Tamb > 40 °C
(depending on other operating
conditions
Storage temperature
-30 °C to +70 °C
Solar module
Maximum short-circuit current
20 A
Maximum open-circuit voltage
60 V DC
Reverse polarity protection at
module input
Up to 36 VDC

Technical data EN
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Battery charging
Type
Lead-acid batteries with gel
(default setting) or liquid elec-
trolyte
Voltage
12 V DC / 24 V DC
Battery I
Battery II
Mixed connection of
12 V and 24 V batteries is only
permitted according to the
adjacent table.
12 V
12 V
24 V1)
24 V1)
12 V
24 V1)
Not permitted! 
The solar charge controller
can be damaged.
24 V
12 V
Line compensation
Automatic compensation of
the charge cut-off voltage by
the voltage drop value deter-
mined across the battery cable
Temperature compensation of
the charge cut-off voltage
-4 mV/K/cell
(initial value at 25 °C)
1 ) Solar module voltage Umpp ≥30 V required

EN Technical data
20 751.792 | Z01 | 1504
Detailed battery charging
data
12 V system
24 V system
Permissible battery voltage
range
9-17 V
17.1-34 V
Deep discharge pre-warning at
12.0 V
24 V
Deep discharge protection at
11.7 V
23.4 V
Switch-on voltage
12.5 V
25 V
Cut-off voltage for float
charge (Float)
14.1 V
28.2 V
Cut-off voltage/activation for
maintenance charge (Boost)
14.4 V /
≤12.7 V
28.8 V /
≤25.4 V
Cut-off voltage/activation for
equalise charge (Equal)
(only with the liquid battery
type setting)
15.0 V /
≤12.2 V
30.0 V /
≤24.4 V
Load circuit
Output voltage
(same as battery I)
12 V DC or 24 V DC
Maximum output current
20 A
Connections
Terminals
for batteries, solar module and
load circuit
USB charge socket
5 V, 1500 mA
Other connections
StecaLink bus system (RJ 45)
Display
LEDs
4 (multicolour)